{"id":6081,"date":"2026-10-19T09:48:27","date_gmt":"2026-10-19T09:48:27","guid":{"rendered":"https:\/\/phd.hi.is\/doktorsvorn\/doktorsvorn-i-lifefnafraedi-jens-gudmundur-hjorleifsson\/"},"modified":"2026-10-19T09:48:27","modified_gmt":"2026-10-19T09:48:27","slug":"doktorsvorn-i-lifefnafraedi-jens-gudmundur-hjorleifsson","status":"publish","type":"phd_defence","link":"https:\/\/phd.hi.is\/en\/doktorsvorn\/doktorsvorn-i-lifefnafraedi-jens-gudmundur-hjorleifsson\/","title":{"rendered":"Doktorsv\u00f6rn \u00ed l\u00edfefnafr\u00e6\u00f0i – Jens Gu\u00f0mundur Hj\u00f6rleifsson"},"content":{"rendered":"
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Doktorsefni:<\/strong> Jens Gu\u00f0mundur Hj\u00f6rleifsson<\/p>\n

Heiti ritger\u00f0ar:<\/strong> Samspil undireininga og \u00e1hrif j\u00f3na \u00e1 kuldavirkan alkal\u00edskan fosfatasa \u00far sj\u00e1var\u00f6rverunni Vibrio splendidus (e.Ionic effects on subunit interactions in a cold-active alkaline phosphatase from the marine bacterium Vibrio splendidus)<\/p>\n

Andm\u00e6lendur:<\/strong>
Dr. Tony Collins, lektor vi\u00f0 Mi\u00f0st\u00f6\u00f0 sameinda- og umhverfisl\u00edffr\u00e6\u00f0i, H\u00e1sk\u00f3lanum \u00ed Minho, Braga, Port\u00fagal.
Dr. Stjepan Orhanovic, d\u00f3sent vi\u00f0 Raunv\u00edsindadeild h\u00e1sk\u00f3lans \u00ed Split, Kr\u00f3at\u00edu.<\/p>\n

Lei\u00f0beinandi:<\/strong> Dr. Bjarni \u00c1sgeirsson, pr\u00f3fessor vi\u00f0 Raunv\u00edsindadeild H\u00e1sk\u00f3la \u00cdslands.<\/p>\n

Einnig \u00ed doktorsnefnd:<\/strong>
Dr. Magn\u00fas M\u00e1r Kristj\u00e1nsson, pr\u00f3fessor vi\u00f0 Raunv\u00edsindadeild H\u00e1sk\u00f3la \u00cdslands.
Dr. Elena Papaleo, d\u00f3sent vi\u00f0 Kaupmannahafnarh\u00e1sk\u00f3la og yfirma\u00f0ur ranns\u00f3knarstofu \u00ed l\u00edfuppl\u00fdsingafr\u00e6\u00f0i vi\u00f0\u00a0Danish Cancer Society Research Center.<\/p>\n

Doktorsv\u00f6rn st\u00fdrir:<\/strong> Dr. Oddur Ing\u00f3lfsson, pr\u00f3fessor og deildarforseti Raunv\u00edsindadeildar H\u00e1sk\u00f3la \u00cdslands.<\/p>\n

\u00c1grip<\/strong>
Fj\u00f3r\u00f0a stigs bygging pr\u00f3teina er grunnur alls l\u00edfs \u00e1 j\u00f6r\u00f0inni eins og vi\u00f0 \u00feekkjum \u00fea\u00f0. Pr\u00f3tein hafa \u00fer\u00f3ast \u00ed \u00e1tt a\u00f0 st\u00f3rum komplexum til a\u00f0 hvata fl\u00f3kin efnahv\u00f6rf, til margv\u00edslegra byggingahlutverka, e\u00f0a h\u00f3lfunar. Flest ens\u00edm eru virk sem ein\u00fe\u00e1tta tv\u00edli\u00f0ur me\u00f0 tv\u00e6r eins hvarfst\u00f6\u00f0var. Hvers vegna svo m\u00f6rg ens\u00edm finnast sem ein\u00fe\u00e1tta tv\u00edli\u00f0ur er ekki vel rannsaka\u00f0. Alkal\u00edskur fosfatasi (AP) er m\u00f3del ens\u00edm fyrir h\u00fddr\u00f3lasa sem eru ein\u00fe\u00e1tta tv\u00edli\u00f0ur. Virkni AP er h\u00e1\u00f0 tv\u00edli\u00f0umyndun og m\u00e1lmj\u00f3num \u00ed hvarfst\u00f6\u00f0. Hvers vegna hvarfst\u00f6\u00f0varnar hafa ekki hvarfgetu \u00ed einli\u00f0uforminu er ekki vita\u00f0. Ranns\u00f3knarefni \u00feessarar doktorsritger\u00f0ar var AP \u00far Vibrio splendidus (VAP) kaldsj\u00e1varbakter\u00edu. VAP er eitt hita\u00f3st\u00f6\u00f0ugasta ens\u00edm sem \u00feekkist en einnig eitt \u00fea\u00f0 virkasta vi\u00f0 l\u00e1g hitastig mi\u00f0a\u00f0 vi\u00f0 samb\u00e6rileg ens\u00edm. \u00c1hersla var l\u00f6g\u00f0 \u00e1 a\u00f0 sk\u00fdra hlutverk tv\u00edli\u00f0umyndunar hj\u00e1 VAP og \u00e1hrif j\u00f3na \u00e1 hv\u00f6tun og st\u00f6\u00f0ugleika, en einnig a\u00f0 \u00fatsk\u00fdra hvers vegna AP hafa ekki virkar einli\u00f0ur. \u00deessir \u00fe\u00e6ttir eru mj\u00f6g h\u00e1\u00f0ir lausnaa\u00f0st\u00e6\u00f0um. Ni\u00f0urst\u00f6\u00f0ur bentu til \u00feess a\u00f0 vi\u00f0 afvirkjun ens\u00edmsins ver\u00f0i \u00f3afturkr\u00e6f myndbreyting sem lei\u00f0ir til \u00f3virkrar tv\u00edli\u00f0u. \u00d3virka tv\u00edli\u00f0an var lausbundnari, innih\u00e9lt allar \u00ferj\u00e1r m\u00e1lmj\u00f3nirnar \u00ed hvarfst\u00f6\u00f0 en haf\u00f0i m\u00f6gulega misst eiginleikann til \u00feess a\u00f0 hvata me\u00f0 svok\u00f6llu\u00f0um \u201chalf-of-sites\u201d hvarfgangi. \u00c1hrif j\u00f3nastyrks voru mikil \u00e1 virkni og st\u00f6\u00f0ugleika og voru \u00e1hrifin h\u00e1\u00f0 pH, \u00fear sem afpr\u00f3t\u00f3nering \u00f3\u00feekkts s\u00fdruh\u00f3p veldur myndbreytingu. A\u00f0 auki var kanna\u00f0 hlutverk l\u00f6ngu yfirbor\u00f0lykkjunnar sem einkennir VAP fr\u00e1 flestum AP. Meginhlutverk lykkjunna er a\u00f0 stu\u00f0la a\u00f0 st\u00f6\u00f0ugleika hvarfst\u00f6\u00f0var en einnig \u00ed a\u00f0 halda \u00e1kve\u00f0inni st\u00edfni \u00ed lykkjum n\u00e1l\u00e6gt virkum hli\u00f0arke\u00f0jum.
Ni\u00f0ursta\u00f0a vinnu \u00feessarar ritger\u00f0ar bendir til \u00feess a\u00f0 meginhlutverk tv\u00edli\u00f0unnar s\u00e9 \u00fea\u00f0 tillegg byggingarfr\u00edorku sem ver\u00f0ur til \u00e1 snertifl\u00f6tum einli\u00f0anna sem stu\u00f0lar b\u00e6\u00f0i a\u00f0 st\u00f6\u00f0ugleika og hv\u00f6tun, sem ekki eru til sta\u00f0ar \u00ed einli\u00f0unum.<\/p>\n

Um doktorsefni\u00f0<\/strong>
Jens er \u00ed samb\u00fa\u00f0 me\u00f0 \u00cdrisi Kristinsd\u00f3ttur og eiga \u00feau saman \u00ferj\u00e1r d\u00e6tur, Sn\u00e6d\u00edsi (f\u00e6dd 2013) og tv\u00edburasysturnar Hei\u00f0bj\u00f6rtu og S\u00f6ru D\u00eds (f\u00e6ddar 2014) .
Jens. lauk BS gr\u00e1\u00f0u \u00ed l\u00edfefnafr\u00e6\u00f0i 2010 og starfa\u00f0i svo \u00e1 ranns\u00f3knarstofu \u00d6lger\u00f0ar Egils Skallagr\u00edmssonar til \u00e1rsins 2012 \u00e1\u00f0ur hann fluttist til Stokkh\u00f3lms \u00ed Sv\u00ed\u00fej\u00f3\u00f0 til a\u00f0 hefja n\u00e1m \u00ed pept\u00ed\u00f0 og pr\u00f3teinefnafr\u00e6\u00f0i vi\u00f0 Stokkh\u00f3lms h\u00e1sk\u00f3la \u00fear sem hann rannsaka\u00f0i m.a. hv\u00f6tunarvirkar DNA kjarns\u00fdrur. Hann lauk MS gr\u00e1\u00f0u \u00e1ri\u00f0 2014 og byrja\u00f0i \u00ed doktorsn\u00e1mi \u00fea\u00f0 sama \u00e1r.<\/p>\n<\/div><\/div>","protected":false},"featured_media":1798,"template":"","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"_phd_date_start":"2018-06-21T10:00:00+00:00","_phd_date_end":"2018-06-21T12:00:00+00:00","_phd_location":"\u00dej\u00f3\u00f0minjasafni\u00f0 - fyrirlestrarsalur","_phd_admission":"Allir velkomnir","_phd_thesis_title":"Samspil undireininga og \u00e1hrif j\u00f3na \u00e1 kuldavirkan alkal\u00edskan fosfatasa \u00far sj\u00e1var\u00f6rverunni Vibrio splendidus (e.Ionic effects on subunit interactions in a cold-active alkaline phosphatase from the marine bacterium Vibrio splendidus)","_phd_source_url":"https:\/\/gamli.hi.is\/vidburdir\/doktorsvorn_i_lifefnafraedi_jens_gudmundur_hjorleifsson","_phd_source_node_id":"311300","_phd_source_type":"vidburdir","_phd_member_id":461,"footnotes":""},"phd_school":[101,93],"phd_discipline":[106],"class_list":["post-6081","phd_defence","type-phd_defence","status-publish","has-post-thumbnail","hentry","phd_school-raunvisindadeild","phd_school-verkfraedi-og-natturuvisindasvid","phd_discipline-phd-i-lifefnafraedi"],"_links":{"self":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence\/6081","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence"}],"about":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/types\/phd_defence"}],"version-history":[{"count":0,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence\/6081\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/media\/1798"}],"wp:attachment":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/media?parent=6081"}],"wp:term":[{"taxonomy":"phd_school","embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_school?post=6081"},{"taxonomy":"phd_discipline","embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_discipline?post=6081"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}